1. Technical Field
The present disclosure relates to coaxial cables and, particularly, to a carbon nanotube based coaxial cable.
2. Discussion of Related Art
Coaxial cables are used as carriers to transfer electrical power and signals. A conventional coaxial cable includes a core, an insulating layer outside the core, and a shielding layer outside the insulating layer, usually surrounded by a sheathing layer. The core includes at least one conducting wire. The conducting wire can be a solid or braided wire, and the shielding layer can, for example, be a wound foil, a woven tape, or a braid. However, as for the conducting wire made of a metal, a skin effect will occur in the conducting wire, thus the effective resistance of the cable becomes larger, and causes signal decay during transmission. Further, the conducting wire and the shielding layer made of metal has less strength for its size, so must be comparatively greater in weight and diameter, and thus in use.
A related art method for making coaxial cable includes the following steps of: coating a polymer on an outer surface of the at least one conducting wire to form an insulating layer; applying a plurality of metal wire or braided metal wire on the insulating layer to form a shielding layer; and covering a sheathing layer on the shielding layer.
Carbon nanotubes (CNTs) are a novel carbonaceous material and received a great deal of interest since the early 1990s. Carbon nanotubes have interesting and potentially useful heat conducting, electrical conducting, and mechanical properties. A conducting wire made by a mixture of carbon nanotubes and metal has been developed. However, the carbon nanotubes in the conducting wire of the prior art are arranged disorderly. Thus, the above-mentioned skin effect has still not been eliminated in coaxial cables employing carbon nanotubes.
What is needed, therefore, is a coaxial cable having good conductivity, high mechanical performance, lightweight and with small diameter to overcome the aforementioned shortcomings.
Corresponding reference characters indicate corresponding parts throughout the several views. The exemplifications set out herein illustrate at least one embodiment of the present coaxial cable and method for making the same, in at least one form, and such exemplifications are not to be construed as limiting the scope of the invention in any manner.